There are all kinds of motivational quotes associated with the phrase ‘finish strong.’ And while not many of them are geared toward decorative concrete, the philosophy applies just the same. After all the time, energy and effort put into a new decorative concrete surface, often there is confusion when it comes to selecting the proper finish. With all the products available and with new products coming on the scene all the time, it can be quite difficult to keep up. Choosing something not suitable for a particular project, or neglecting the top coat all together, leaves the beauty of the decorative concrete to slowly wear away and all the hard work of installing the decorative concrete to be for not.
The end use of the floor is the single most important factor in choosing a top coat. The important things to consider are the amount and type of traffic, the location (interior or exterior) the maintenance schedule, and the desired appearance. Secondary considerations for choosing the best top coat are the application requirements, the budget, and the desired longevity. With these factors in mind, we can then look at the basic characteristics of the four general categories of top coats to try and find the best match. Here are some typical properties each:
Acrylic Epoxy Polyurethane Polyaspartic
Traffic: light heavy heavy /commercial heavy /industrial
Uses: indoor/outdoor indoor indoor indoor/outdoor
Skill Level: low medium high high
Durability: low medium high highest
Pot Life: / short long short
Surface Build: low high low varies by product
Make up: 1 part 2 parts 2 parts 2 parts
Aggregates: no yes no no
Chemical Resist.: no yes yes yes
UV Stable: yes no yes yes
Cost: low medium high highest
Base: water /solvent water / solvent solvent solvent
Synopsis:
Acrylics are the cheapest and easiest to install. They work indoors and outdoors. They are a low surface build and offer low protection to any type of heavy traffic. They are installed with a brush, roller, or low pressure sprayer. They need to be re-applied often or protected with a floor wax.
Epoxies are usually more expensive than acrylics and because they are two part systems with a resin and curing agent, they can be more difficult to install. They offer high surface build and can be used with aggregate additives like glass, sand, color flakes, or metallics. They are installed with a trowel, gauge rake, or squeegee. They typically have a short pot life. They have great adhesion but can yellow with UV exposure. The surface is very hard which makes them suitable for vehicle and heavy traffic in retail spaces. Because they can scratch and the surface can lose its shine, they are often coated with polyurethanes or are used with routine floor waxing to protect the surface.
Polyurethanes are more expensive than epoxies. They are usually only used indoors and are also two part systems. They are a lower build and are often applied in two coats of 2-3 mils. Installation is with a brush, roller, or airless sprayer. They have a longer pot life, but can still be tricky to install. They are very durable and are suitable for high traffic areas including commercial and industrial. They have a hard surface that is scratch resistant, stain resistant and chemical resistant.
Polyaspartics are the most expensive and can be the most difficult to install due to their very short pot life, fast cure times and surface preparation requirements. They are low surface build, but are usually installed in multiple coats with a roller, squeegee or sprayer. They are UV stable and have an extremely durable, chemical and stain resistant surface making them a great choice for very high traffic areas, including commercial and industrial spaces. They can be applied in a wide range of temperatures and their quick cure times allow spaces to be returned to use much faster than other coatings which can sometimes offset the additional cost.